#include <stdio.h>
#include <stdlib.h>
int main(void)
{
    FILE *fp;
    if ((fp = fopen("flushtest", "w+")) == NULL)
    {
        printf("Cannot open file.\n");
        exit(1);
    }
    char ch = 'C';
    int i;
    for (i = 0; i < 5; i++)
    {
        fwrite(&ch, sizeof(ch), 1, fp);
        printf("hello flush\n");
        fflush(fp);

        sleep(2);
    }
    fclose(fp);
    return 0;
}
